-> ,validPeriod= 2015 Nobel Prize in physics - announcement of the winners of the (TT NEWS AGENCY / REUTERS / REUTERS) 2 -> neutrinos behave like phantoms in the world of matter. As today we know with certainty, every second by our bodies penetrate billions of these particles, but in general do not feel. We are for them almost completely see-through. Estimates indicate that in order to be sure to capture neutrinos, on his way need to set the wall with a lead lining one light-year, ie. 10 trillion km. It is no wonder that this particle was discovered for the first time ... paper. In the 30th century, physicists in the calculations simply disagreed with the energy balance of the decay of radioactive one. The initial state different from the end, that is the reaction perished some energy. Some even want to have to come to terms with the fact that we are dealing with a violation of the basic laws of nature - the principle of conservation of energy. And then the German physicist Wolfgang Pauli in desperation, came up with it all goes wrong, if the reaction produces hitherto unknown particle and escapes unnoticed. This is why this energy wastage. Apparently Paula very this worrying: "I did a terrible thing, came up with a piece that can not be detected." A bag with noblami It was called a neutrino and started searching. The hunt lasted until a quarter-century, succeeded only in the mid 50s, when the neutrino detector is set just behind one of the first nuclear reactor, which produced a huge stream of these particles. The discovery of neutrinos after half a century, in 1995, r., he was awarded the Nobel Prize (it only picked up one of the discoverers, the second died 21 years earlier). It was not the first Nobel award in this field. A few years earlier - in 1988. - They got the Nobel Prize physicists, who in the 60s of the last century have discovered that there is more than one type of neutrino. In addition to neutrinos, which always occurs in tandem with an electron (ie. An electron neutrino), there is also the neutrinos associated with heavier cousin of the electron - muon. It muon neutrinos. Then it turned out that the electron has another heavier cousin called tau. Which meant that the steam is also the tau neutrino. In all we know so today three types of neutrinos. The theory of the structure of matter - the so-called. The Standard Model - said that they are devoid of weight (like electromagnetic radiation particles - photons), and that the Big Bang was born a lot of them (hundreds of millions in every cubic meter of space). And because they still occur in places where nuclear reactions are ubiquitous. Only photons are today in the Universe more. 60 billion per square centimeter A big source of these particles we have right under our noses, because nuclear fusion reactions inside the sun constantly arise electron neutrinos. Their very abundant stream - approx. 60 billion per square centimeter! - Should bomb and literally pierce Earth. And that was associated with them another great mystery. Already in the late 60s of the last century failed to detect electron neutrinos with this powerful river flowing from the Sun, but there were not enough. Three times less than the result from the calculation. Astrophysicists were amazed, because it could mean that we do not understand exactly what happens inside stars. On the site there were many fantastic theories. According to one of them, the source of solar energy were to be no thermonuclear reactions, but the black hole, which is located in the center of the star. Most physicists considered, however, that the Sun is all right. It neutrinos must behave differently than theory predicted. It was suggested that during the journey from the Sun neutrinos change their identity - these electron transform into muon, muon into tau, etc., As permitted by quantum mechanics. This hypothesis was called neutrino oscillations. He explains why the Earth reaches only a third of electron neutrinos. The rest of the fly changes "skin" or - as they say professional physicists - "smell". If we have taken into account in measuring other types of neutrinos, the balance would agree. But until recently no one was able to do so. Evidence of the changing nature of neutrinos found only at the turn of the century. I made this year's Nobel Prize winners who zaczaili on neutrinos in old mine shafts in Japan and Canada. Japanese trap neutrino traps usually placed deep underground to eliminate any possible interference. The first was established in the mountains north of Tokyo, a kilometer below the surface, in an old zinc mine tunnels. Japanese detector Super-Kamiokande measure there stream muon, which are formed by collisions of cosmic rays with the Earth's atmosphere. Super-Kamiokande detected neutrinos that were coming directly from above, and from below, ie those which formed in the atmosphere at the antipodes, on the other side of the Earth (neutrinos without obstacles overcome because the whole planet). It turned out that the bottom is less, and this meant that the road through the center of the Earth muon neutrinos transformed into some other, probably tau. Canadian hunting Another evidence of neutrino oscillations, this time those of the Sun was obtained in the Canadian Sudbury Neutrino Observatory (SNO). There was created a trap, which counts all the neutrinos arriving from the Sun: electron, muon and tau. When, in 2002. Physicists summed up the results of measurements, they could crack open the champagne. The mystery of the solar neutrino deficiency is explained. The total number of neutrinos - of all types - arriving from the sun disagreed with the accounts. She was three times greater than the measured years before the electron neutrino flux. As suspected, as many as two-thirds of these particles in flight turns into muon neutrinos and tau. This caused another sensation. Neutrino oscillation is possible only in one case - if neutrinos have mass. At least not yet been able to accurately measure. We only know that it is not large. Neutrinos are at least several hundred times lighter than an electron, hitherto regarded as the lightest particle. But since it is their space such swarms, their total mass may weigh on the fate of the universe. What is more, however, the discovery that neutrinos have mass, was the first crack in the modern theory of the structure of matter, which indicated that The Standard Model needs to be supplemented. Or replace it with a better theory, preferably one that would correspond to some weighty questions. Why are light neutrinos? Are there only three types (according to some hypotheses may be a fourth called. Sterile neutrino)? Are they in themselves their own antiparticles (as possible)? And why are so very different from other particles of matter? What it can be used Fascinating is also the neutrinos into something useful useful. One application already know - observation of the interior of the sun. Neutrinos fly out of there without any obstacles, so you can use them to look from the very center of the star. Neutrino, which is born in the middle of our parent star, reaches the Earth after just 8.3 minutes, while photons (which interact with other particles) have to be there to wade toward the surface of the star thousands of years. neutrinom can also explore supernova explosions, collisions of neutron stars and other cosmic cataclysms nuclear, which are produced powerful jets of particles. Neutrinos are moving quickly and the simplest way to Earth, easily penetrate the interstellar clouds, stars and galaxies. They are so perfect witness distant events. The first attempts to neutrino astrophysics - the pioneering measurements of neutrinos from the Sun and supernova SN 1987A (in the detector Kamiokande, the predecessor of the Super-Kamiokande) - in 2002. Have been awarded the Nobel Prize and It probably will not be the last prize associated with neutrinos. One of the observatories of the particles formed recently under the ice of Antarctica, the other at the bottom of the Mediterranean. Stanislaw Lem predicted that alien civilizations could use these particles in interstellar communication. There are still almost as fast as the radio waves, but unlike the latter are not to block out and not to stop. In the "Voice of the Lord" Lem described the character of the eccentric scientist who for years insisted that the stream of neutrinos reaching Earth discovered a coded signal. Perhaps this vision will soon come true. In 2012,. American scientists from the center Fermilab in Chicago managed to send the first message using neutrinos. It read - and it's not hard to guess - "neutrino". Who knows, maybe our future smartphones will run not by radio waves, but thanks neutrinom? Subscription to digital Electoral available via the Internet, phone, tablet and eReader from 17.90 per month To assess login or zarejestrujX
Why so look for?
The Nobel Committee praised the scientists were able to discover one of the secrets of neutrinos - the most elusive particles in the Universe.
Further puzzles
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